'Mulberry trees' in the Bible

And when you hear the sound of marching in the tops of the balsam trees, then you shall pay attention and act promptly, for at that time the Lord will have gone out before you to strike the army of the Philistines.”

So David inquired again of God, and God said to him, “Do not go up after them; circle around behind them and come at them in front of the balsam trees.